EDIT: Resuggesting since it would convert into keys, and its actually 18-19 rather than 18-20

Fixing dat flat price I made :3

Proof below. Overpay calculated

Sales

http://www.tf2outpost.com/trade/14209932 - Blizz Football Helmet = 18 keys

Side note: Took mid price since it was offered on

http://www.tf2outpost.com/trade/14596945 - Bubbling Hermes, other guy added 2 keys = 19 keys

Side note: Took mid price since it was offered on

http://www.tf2outpost.com/trade/14474100 - Bubbling Pyro's Beanie + 1 key = 19 keys

http://www.tf2outpost.com/trade/14292603 - 16 keys + a S. Degreaser with parts (~3 keys) = 19 keys

http://www.tf2outpost.com/trade/14362882 - Bubbling Bonnet = 19 keys

Side note: Took mid price since it was offered on

B/O's

http://www.tf2outpost.com/trade/14399913 - 1 bud

http://www.tf2outpost.com/trade/14707332 - 18 keys

http://www.tf2outpost.com/trade/14636301 - 1 bud

http://www.tf2outpost.com/trade/14798195 - 16/17 keys (not included in the range due to sales at higher prices)

Conclusion

So many sales O_o Meh, vote accordingly :3

Help / Constructive Criticism / Additional Proof / Counter-Proof is ALWAYS welcome! >;3